#include<iostream>
#include<string>

using namespace std;

int main(){

	string s1;

	s1="Hello wooooorld";
	s1.erase();
	cout<<s1<<endl;


	s1="Hello wooooorld";
	s1.erase(7);
	cout<<s1<<endl;

	s1="Hello woooorld";
	s1.erase(7,3);
	cout<<s1<<endl;


	s1="Hello woooorld";
	s1.erase(s1.begin());
	cout<<s1<<endl;

	s1="Hello woooorld";
	s1.erase(s1.begin()+7,s1.begin()+10);
	cout<<s1<<endl;

	return 0;


}
